Serum CC-Chemokine Ligand 2 Is Associated with Visceral Adiposity but Not Fibrosis in Patients with Non-Alcoholic Fatty Liver Disease.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is caused by ectopic fat accumulation in the liver as a consequence of metabolic perturbations associated with obesity, type 2 diabetes, dyslipidemia, and insulin resistance. People with NAFLD may develop metabolic and cardiovascular complications and/or liver-related complications, especially fibrosis and hepatocellular carcinoma, associated with high morbidity and mortality. Due to the high and increasing prevalence of NAFLD, there is an urgent need to identify people at risk of developing liver fibrosis and complications. CC-chemokine ligand 2 (CCL2) is chemokine that attracts inflammatory monocytes to stressed or injured tissues. Infiltrating inflammatory monocytes and CCL2 are strongly implicated in the pathogenesis of liver disease in animal models; however, evidence in patient cohorts is conflicting. METHODS: We investigated associations between circulating CCL2 and clinical parameters, including fibrosis assessed by liver stiffness measurement, in a cohort of 250 NAFLD patients. We also measured fatty acid binding protein 2 (FABP2), a putative biomarker of intestinal permeability in patients with liver disease, since pro-inflammatory gut-derived microbial products may induce inflammatory chemokines such as CCL2. RESULTS: Serum CCL2 levels were weakly associated with liver stiffness, but the association was no longer significant after accounting for age, diabetes, and BMI in a multivariable model. Consistent with this, girth and BMI were the strongest predictors of elevated circulating CCL2. Serum FABP2 was weakly, but significantly, correlated with CCL2, and negatively correlated with estimated glomerular filtration rate. CONCLUSION: Circulating CCL2 and FABP2 are associated with NAFLD comorbidities but not liver disease progression in patients with NAFLD.

Wernicke's encephalopathy in advanced cancer.

This 54-year-old woman with metastatic breast cancer presented with severe confusion, incontinence and self-neglect. MRI suggested Wernicke's encephalopathy (WE) without any history of alcohol misuse. The patient's symptoms seemed to not respond to acute treatment. Cancer progression was assumed to be causing her condition and she was discharged to a nursing home with community palliative care team follow-up. This case demonstrates the natural course of cancer-associated WE and eventual improvement with thiamine therapy. It also illustrates a role for specialist palliative care follow up for patients discharged to a nursing home for expected end-of-life care.

Discovery of protein-based natural hydrogel from the girdle of the 'sea cockroach' Chiton articulatus (Chitonida: Chitonidae).

Hydrogels are widely used materials in biomedical, pharmaceutical, cosmetic, and agricultural fields. However, these hydrogels are usually formed synthetically via a long and complicated process involving crosslinking natural polymers. Herein, we describe a natural hydrogel isolated using a 'gentle' acid treatment from the girdle of a chiton species (Chiton articulatus). This novel hydrogel is shown to have a proliferative effect on mouse fibroblast cells (cell line, L929). The swelling capacity of this natural hydrogel was recorded as approximately 1,200% in distilled water, which is within desired levels for hydrogels. Detailed characterizations reveal that the hydrogel consists predominantly (83.93%) of protein. Considering its non-toxicity, proliferative effect and swelling properties, this natural hydrogel is an important discovery for material sciences, with potential for further applications in industry. Whether the girdle has some hydrogel activity in the living animal is unknown, but we speculate that it may enable the animal to better survive extreme environmental conditions by preventing desiccation.

Implementing the right care in the right place at the right time for non-alcoholic fatty liver disease (NAFLD-RRR study): a study protocol for a community care pathway for people with type 2 diabetes.

BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is an emerging epidemic that affects approximately half of all people with type 2 diabetes. Those with type 2 diabetes are a high-risk NAFLD subgroup because of their increased risk of clinically significant liver-related outcomes from NAFLD which include hepatocellular carcinoma, cirrhosis-related complications and liver disease mortality. They may benefit from early detection of disease as this would allow at risk patients to access hepatocellular carcinoma surveillance, emerging drug trials for NAFLD and specialist hepatology care prior to emergence of liver-related complications. METHODS: This is a prospective cohort study aimed at incorporating and assessing a community care pathway for liver fibrosis screening into routine care for type 2 diabetes. Patients undergo a point of care assessment of hepatic steatosis and stiffness using FibroScan at the time of the routine diabetes appointment or when attending the clinic for blood tests in preparation for this appointment. DISCUSSION: We propose that implementation of a community-based NAFLD diagnosis, risk-stratification, and referral pathway for people with type 2 diabetes is feasible, will provide earlier, targeted detection of advanced fibrosis, and reduce unnecessary referrals to hepatology outpatients for fibrosis risk assessment. Our study will provide important information about the feasibility of establishing a NAFLD pathway for people with type 2 diabetes in primary care. Ultimately, our findings will help direct spending and resource allocation for NAFLD in a high-risk population. Regular evaluation by stakeholders during implementation will help to create a reliable and sustainable community care pathway and establish a perpetual cycle of learning in primary care. TRIAL REGISTRATION: ANZCTR, ACTRN12621000330842 . Registered 23 March 2021.

Impact of afterload and infiltration on coexisting aortic stenosis and transthyretin amyloidosis.

OBJECTIVE: The coexistence of wild-type transthyretin cardiac amyloidosis (ATTR) is common in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI). However, the impact of ATTR and AS on the resultant AS-ATTR is unclear and poses diagnostic and management challenges. We therefore used a multicohort approach to evaluate myocardial structure, function, stress and damage by assessing age-related, afterload-related and amyloid-related remodelling on the resultant AS-ATTR phenotype. METHODS: We compared four samples (n=583): 359 patients with AS, 107 with ATTR (97% Perugini grade 2), 36 with AS-ATTR (92% Perugini grade 2) and 81 age-matched and ethnicity-matched controls. 99mTc-3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) scintigraphy was used to diagnose amyloidosis (Perugini grade 1 was excluded). The primary end-point was NT-pro Brain Natriuretic Peptide (BNP) and secondary end-points related to myocardial structure, function and damage. RESULTS: Compared with older age controls, the three disease cohorts had greater cardiac remodelling, worse function and elevated NT-proBNP/high-sensitivity Troponin-T (hsTnT). NT-proBNP was higher in AS-ATTR (2844 (1745, 4635) ng/dL) compared with AS (1294 (1077, 1554)ng/dL; p=0.002) and not significantly different to ATTR (3272 (2552, 4197) ng/dL; p=0.63). Diastology, hsTnT and prevalence of carpal tunnel syndrome were statistically similar between AS-ATTR and ATTR and higher than AS. The left ventricular mass indexed in AS-ATTR was lower than ATTR (139 (112, 167) vs 180 (167, 194) g; p=0.013) and non-significantly different to AS (120 (109, 130) g; p=0.179). CONCLUSIONS: The AS-ATTR phenotype likely reflects an early stage of amyloid infiltration, but the combined insult resembles ATTR. Even after treatment of AS, ATTR-specific therapy is therefore likely to be beneficial.

Fitting Health Care to People: Understanding and Adapting to the Epidemiology and Health Literacy of People Affected by Viral Hepatitis from Culturally and Linguistically Diverse Migrant Backgrounds.

This study explored the epidemiology and health literacy of people affected by viral hepatitis (VH) from migrant culturally and linguistically diverse (CALD) backgrounds attending a community-based general practitioner and specialty hepatology shared-care (HEPREACH) clinic in Brisbane, Australia. Patient-reported data on health literacy and clinical information from adult patients (n = 66) of CALD background recruited from the liver clinic were analyzed. Health literacy was assessed using a 5-question, 12-point scale. Variance weighted multiple linear regression was used to identify factors associated with knowledge about VH. About three-quarters of patients (74.2%) were diagnosed with hepatitis B. The median knowledge score was 7.8 (interquartile range [IQR] 6‒9). One in five patients did not understand the infective nature of VH, 30.3% did not understand mother-to-child transmission risk, and 30-40% of patients thought activities such as kissing, sharing food or mosquito bites could spread VH. Only 6% of patients understood the risk of liver cancer and the need for regular screening. Higher educational level (secondary, ß = 4.8, p < 0.0001 or tertiary, ß = 8.1, p < 0.0001 vs. primary) was associated with better knowledge, and transition through a refugee camp (vs. not, ß = - 1.2, p = 0.028) and country of diagnosis (overseas vs. Australia, ß = - 1.9, p = 0.016) were associated with poorer knowledge. Country of origin, refugee status and opportunities for tertiary education impact patients' understanding of VH. Ensuring delivery of culturally appropriate care and education is critical to improve knowledge, reduce misconceptions to improve care and outcomes for VH in CALD migrant communities.

Serum matrix metalloproteinase 7 (MMP7) is a biomarker of fibrosis in patients with non-alcoholic fatty liver disease.

Non-alcoholic fatty liver disease (NAFLD) affects 25% of the adult population globally. Since liver fibrosis is the most important predictor of liver-related complications in patients with NAFLD, identification of patients with advanced fibrosis among at-risk individuals is an important issue in clinical practice. Transient elastography is the best evaluated non-invasive method used in referral centres to assess liver fibrosis, however serum-based tests, such as the Enhanced Liver Fibrosis (ELF) score, have a practical advantage as first-line tests due to their wider availability and lower cost. We previously identified matrix metalloproteinase 7 (MMP7) as a serum biomarker of histological advanced fibrosis in a mixed-etiology patient cohort. In this study we aimed to determine the association between MMP7 and fibrosis, assessed by transient elastography, in patients with NAFLD. Serum MMP7 levels were measured in a cohort of 228 patients with NAFLD. Associations between MMP7, liver stiffness measurement (LSM), ELF score and clinical parameters were determined using logistic regression modelling. Serum MMP7 was associated with clinically significant fibrosis (LSM ≥ 8.2), independent of age, gender, BMI and diabetes. The addition of MMP7 significantly improved the diagnostic performance of the ELF test, particularly in patients over the age of 60. Combinations of serum biomarkers have the potential to improve the sensitivity and specificity of detection of advanced fibrosis in at-risk patients with NAFLD. We have demonstrated that serum MMP7 is independently associated with clinically significant fibrosis and improves the diagnostic performance of currently available tests in older patients.

Type 2 diabetes does not account for ethnic differences in exercise capacity or skeletal muscle function in older adults.

AIMS/HYPOTHESIS: The aim of this study was to compare exercise capacity, strength and skeletal muscle perfusion during exercise, and oxidative capacity between South Asians, African Caribbeans and Europeans, and determine what effect ethnic differences in the prevalence of type 2 diabetes has on these functional outcomes. METHODS: In total, 708 participants (aged [mean±SD] 73 ± 7 years, 56% male) were recruited from the Southall and Brent Revisited (SABRE) study, a UK population-based cohort comprised of Europeans (n = 311) and South Asian (n = 232) and African Caribbean (n = 165) migrants. Measurements of exercise capacity using a 6 min stepper test (6MST), including measurement of oxygen consumption ([Formula: see text]) and grip strength, were performed. Skeletal muscle was assessed using near infrared spectroscopy (NIRS); measures included changes in tissue saturation index (∆TSI%) with exercise and oxidative capacity (muscle oxygen consumption recovery, represented by a time constant [τ]). Analysis was by multiple linear regression. RESULTS: When adjusted for age and sex, in South Asians and African Caribbeans, exercise capacity was reduced compared with Europeans ([Formula: see text] [ml min-1 kg-1]: ß = -1.2 [95% CI -1.9, -0.4], p = 0.002, and ß -1.7 [95% CI -2.5, -0.8], p < 0.001, respectively). South Asians had lower and African Caribbeans had higher strength compared with Europeans (strength [kPa]: ß = -9 [95% CI -12, -6), p < 0.001, and ß = 6 [95% CI 3, 9], p < 0.001, respectively). South Asians had greater decreases in TSI% and longer τ compared with Europeans (∆TSI% [%]: ß = -0.9 [95% CI -1.7, -0.1), p = 0.024; τ [s]: ß = 11 [95% CI 3, 18], p = 0.006). Ethnic differences in [Formula: see text] and grip strength remained despite adjustment for type 2 diabetes or HbA1c (and fat-free mass for grip strength). However, the differences between Europeans and South Asians were no longer statistically significant after adjustment for other possible mediators or confounders (including physical activity, waist-to-hip ratio, cardiovascular disease or hypertension, smoking, haemoglobin levels or ß-blocker use). The difference in ∆TSI% between Europeans and South Asians was marginally attenuated after adjustment for type 2 diabetes or HbA1c and was also no longer statistically significant after adjusting for other confounders; however, τ remained significantly longer in South Asians vs Europeans despite adjustment for all confounders. CONCLUSIONS/INTERPRETATION: Reduced exercise capacity in South Asians and African Caribbeans is unexplained by higher rates of type 2 diabetes. Poorer exercise tolerance in these populations, and impaired muscle function and perfusion in South Asians, may contribute to the higher morbidity burden of UK ethnic minority groups in older age.

A Pragmatic Approach Identifies a High Rate of Nonalcoholic Fatty Liver Disease With Advanced Fibrosis in Diabetes Clinics and At-Risk Populations in Primary Care.

Noninvasive serum biomarkers (nonalcoholic fatty liver disease fibrosis score [NFS], fibrosis 4 score [FIB-4], or enhanced liver fibrosis [ELF] test) are recommended as first-line tools to determine the risk of advanced fibrosis in nonalcoholic fatty liver disease. We aimed to assess the utility of a pragmatic approach to screening for clinically significant fibrosis in primary care and diabetes clinics. We recruited 252 patients from an endocrine clinic or primary care facility. Anthropometric measurements, ELF test, ultrasound, and liver stiffness measurements (LSMs) were performed. Clinically significant fibrosis was defined as LSM ≥8.2 kPa or ELF ≥9.8. A subgroup of patients underwent liver biopsy (n = 48) or had imaging diagnostic of cirrhosis (n = 14). Patients were 57.3 ± 12.3 years old with a high prevalence of metabolic syndrome (84.5%), type 2 diabetes (82.5%), and body mass index (BMI) ≥40 kg/m2 (21.8%). LSM met quality criteria in 230 (91.3%) patients. NFS and FIB-4 combined had a high negative predictive value (90.0%) for excluding LSM ≥8.2 kPa. However, 84.1% of patients had indeterminate or high NFS or FIB-4 scores requiring further assessment. LSM ≥8.2 kPa and ELF ≥9.8 were present in 31.3% and 28.6% of patients, respectively. Following adjustment for age, BMI, sex, and presence of advanced fibrosis, older age was independently associated with ELF ≥9.8 (adjusted odds ratio, 1.14; 95% confidence interval, 1.06-1.24), whereas increasing BMI was independently associated with LSM ≥8.2 kPa (adjusted odds ratio, 1.15; 95% confidence interval, 1.01-1.30). Concordant LSM <8.2 kPa and ELF <9.8 and concordant LSM ≥8.2 kPa and ELF ≥9.8 had a high negative predictive value (91.7%) and positive predictive value (95.8%) for excluding and identifying clinically significant fibrosis, respectively. Conclusion: Simple scoring tools alone lack accuracy. LSM accuracy is influenced by severe obesity, whereas age impacts the ELF test. Further studies are required to confirm whether combining LSM and ELF may enhance accuracy and confidence in identifying clinically significant fibrosis. (Hepatology Communications 2018; 00:000-000).

Controlled attenuation parameter in NAFLD identifies risk of suboptimal glycaemic and metabolic control.

AIMS: To examine the relationship between steatosis quantified by controlled attenuation parameter (CAP) values and glycaemic/metabolic control. METHODS: 230 patients, recruited from an Endocrine clinic or primary care underwent routine Hepatology assessment, with liver stiffness measurements and simultaneous CAP. Multivariable logistic regression was performed to identify potential predictors of Metabolic Syndrome (MetS), HbA1c ≥ 7%, use of insulin, hypertriglyceridaemia and CAP ≥ 300 dB/m. RESULTS: Patients were 56.7 ±â€¯12.3 years of age with a high prevalence of MetS (83.5%), T2DM (81.3%), and BMI ≥ 40 kg/m2 (18%). Median CAP score was 344 dB/m, ranging from 128 to 400 dB/m. BMI (aOR 1.140 95% CI 1.068-1.216), requirement for insulin (aOR 2.599 95% CI 1.212-5.575), and serum ALT (aOR 1.018 95% CI 1.004-1.033) were independently associated with CAP ≥ 300 dB/m. Patients with CAP interquartile range < 40 (68%) had a higher median serum ALT level (p = 0.029), greater prevalence of BMI ≥ 40 kg/m2 (p = 0.020) and higher median CAP score (p < 0.001). Patients with higher CAP scores were more likely to have MetS (aOR 1.011 95% CI 1.003-1.019), HBA1c ≥ 7 (aOR 1.010 95% CI 1.003-1.016), requirement for insulin (aOR 1.007 95% CI 1.002-1.013) and hypertriglyceridemia (aOR 1.007 95% CI 1.002-1.013). CONCLUSIONS: Our data demonstrate that an elevated CAP reflects suboptimal metabolic control. In diabetic patients with NAFLD, CAP may be a useful point-of-care test to identify patients at risk of poorly controlled metabolic comorbidities or advanced diabetes.

Alcohol Consumption in Diabetic Patients with Nonalcoholic Fatty Liver Disease.

AIM: To examine the association between lifetime alcohol consumption and significant liver disease in type 2 diabetic patients with NAFLD. METHODS: A cross-sectional study assessing 151 patients with NAFLD at risk of clinically significant liver disease. NAFLD fibrosis severity was classified by transient elastography; liver stiffness measurements ≥8.2 kPa defined significant fibrosis. Lifetime drinking history classified patients into nondrinkers, light drinkers (always ≤20 g/day), and moderate drinkers (any period with intake >20 g/day). RESULT: Compared with lifetime nondrinkers, light and moderate drinkers were more likely to be male (p = 0.008) and to be Caucasian (p = 0.007) and to have a history of cigarette smoking (p = 0.000), obstructive sleep apnea (p = 0.003), and self-reported depression (p = 0.003). Moderate drinkers required ≥3 hypoglycemic agents to maintain diabetic control (p = 0.041) and fibrate medication to lower blood triglyceride levels (p = 0.044). Compared to lifetime nondrinkers, light drinkers had 1.79 (95% CI: 0.67-4.82; p = 0.247) and moderate drinkers had 0.91 (95% CI: 0.27-3.10; p = 0.881) times the odds of having liver stiffness measurements ≥8.2 kPa (adjusted for age, gender, and body mass index). CONCLUSIONS: In diabetic patients with NAFLD, light or moderate lifetime alcohol consumption was not significantly associated with liver fibrosis. The impact of lifetime alcohol intake on fibrosis progression and diabetic comorbidities, in particular obstructive sleep apnea and hypertriglyceridemia, requires further investigation.

Multimorbidity and polypharmacy in diabetic patients with NAFLD: Implications for disease severity and management.

An observational study describing the number and type of chronic conditions and medications taken by diabetic patients with NAFLD and identifying characteristics that may impact liver disease severity or clinical management.Adults with type 2 diabetes have a high prevalence of nonalcoholic fatty liver disease (NAFLD) and increased risk of developing advanced liver disease. Appropriate management should consider the characteristics of the diabetic NAFLD population, as comorbid conditions and medications may increase the complexity of treatment strategies.Diabetic patients with NAFLD at risk of clinically significant liver disease (as assessed by the FIB-4 or NAFLD fibrosis scores) were recruited consecutively from the Endocrine clinic or primary care. Medical conditions, medication history, anthropometric measurements, and laboratory tests were obtained during assessment. NAFLD severity was classified by transient elastography and liver ultrasound into "no advanced disease" (LSM < 8.2 kPa) or "clinically significant liver disease" (LSM ≥ 8.2 kPa).The most common coexistent chronic conditions were metabolic syndrome (94%), self-reported "depression" (44%), ischaemic heart disease (32%), and obstructive sleep apnoea (32%). Polypharmacy or hyperpolypharmacy was present in 59% and 31% of patients respectively. Elevated LSM (≥ 8.2 kPa) suggesting significant liver disease was present in 37% of this at-risk cohort. Increasing obesity and abdominal girth were both independently associated with likelihood of having significant liver disease.There is a high burden of multimorbidity and polypharmacy in diabetic NAFLD patients, highlighting the importance of multidisciplinary management to address their complex health care needs and ensure optimal medical treatment.

CYP19A1 single nucleotide polymorphism associations with CYP19A1, NFκB1, and IL6 gene expression in human normal colon and normal liver samples.

BACKGROUND: Estrogen is known to decrease the risk of colon cancer in postmenopausal women, and may exert its actions by decreasing interleukin-6 (IL6) production via stabilization of the transcription factor nuclear factor kappa-light-chain-enhancer of activated B cells (NFκB). Estrogens are biosynthesized by CYP19A1 (aromatase), so it is possible that genetic variations in CYP19A1 influences the risk of colon cancer by altering expression of CYP19A1. Further, studies on gene-gene interactions suggest that single nucleotide polymorphisms in one gene may affect expression of other genes. The current study aims to explore the role of CYP19A1 single nucleotide polymorphisms on CYP19A1, NFκB1 and IL6 gene expression. METHODS: Phenotype-genotype associations, cross-associations between genes, and haplotype analyses were performed in both normal human colon (n=82) and liver (n=238) samples. RESULTS: CYP19A1 rs10459592, rs1961177, and rs6493497 were associated with CYP19A1 expression in colon samples (P=0.042, P=0.041, and P=0.013, respectively). CYP19A1 single nucleotide polymorphisms (rs12908960, rs730154, rs8025191, and rs17523880) were correlated with NFκB1 expression (P=0.047, P=0.04, P=0.05, and P=0.03, respectively), and CYP19A1 rs11856927, rs2470152, and rs2470144 (P=0.049, P=0.025, P=0.047, respectively) were associated with IL6 expression in the colon. While rs730154 and rs17523880 could not be analyzed in the liver samples, none of the other associations with the colon were replicated in the liver samples. Haplotype analysis revealed three separate haplotypes of the CYP19A1 single nucleotide polymorphism that were significantly associated with CYP19A1, NFκB1, and IL6 gene expression. CONCLUSION: CYP19A1 single nucleotide polymorphisms are associated not only with CYP19A1 expression but also with NFκB1 and IL6 expression. These data demonstrate the possible functional consequences of genetic variation within the CYP19A1 gene on other genes in a biologically plausible pathway.

Sulfotransferase 1A1 (SULT1A1) gene expression is regulated by members of the NFI transcription factors in human breast cancer cells.

BACKGROUND: Sulfotransferase 1A1 (SULT1A1) gene expression is tissue specific, with little to no expression in normal breast epithelia. Expression in breast tumors has been documented, but the transcriptional regulation of SULT1A1 in human breast tissue is poorly understood. We identified Nuclear Factor I (NFI) as a transcription factor family involved in the regulation of SULT1A1 expression. METHODS: Transcription Factor Activation Profiling Plate Array assay was used to identify the possible transcription factors that regulate the gene expression of SULT1A1in normal breast MCF-10A cells and breast cancer ZR-75-1 cells. Expression levels of NFI-C and SULT1A1 were determined by real-time RT-PCR using total RNA isolated from 84 human liver samples. Expression levels of SULT1A1, NFI-A, NFI-B, NFI-C, and NFI-X were also determined in different human breast cancer cell lines (MCF-7, T-47D, ZR-75-1, and MDA-MB-231), in the transformed human epithelial cell line MCF-10A, and in ZR-75-1 cells that were transfected with siRNAs directed against NFI-A, NFI-B, NFI-C, or NFI-X for 48 h. The copy numbers of SULT1A1 in cell lines ZR-75-1, MCF-7, T-47D, MDA-MB-231, and MCF-10A were determined using a pre-designed Custom Plus TaqMan® Copy Number kit from Life Technologies. RESULTS: In normal human liver samples, SULT1A1 mRNA level was positively associated with NFI-C. In different human breast cancer and normal epithelial cell lines, SULT1A1 expression was positively correlated with NFI-B and NFI-C. SULT1A1 expression was decreased 41% and 61% in ZR-75-1 cells treated with siRNAs against NFI-A and NFI-C respectively. SULT1A1 gene expression was higher in cells containing more than one SULT1A1 copy numbers. CONCLUSIONS: Our data suggests that SULT1A1 expression is regulated by NFI, as well as SULT1A1 copy number variation in human breast cancer cell lines. These data provide a mechanistic basis for the differential expression of SULT1A1 in different tissues and different physiological states of disease.

Fulvestrant up regulates UGT1A4 and MRPs through ERα and c-Myb pathways: a possible primary drug disposition mechanism.

Fulvestrant (Faslodex™) is a pure antiestrogen that is effective in treating estrogen receptor-(ER) positive breast cancer tumors that are resistant to selective estrogen receptor modulators such as tamoxifen. Clinical trials investigating the utility of adding fulvestrant to other therapeutics have not been shown to affect cytochrome P450-mediated metabolism. Effects on phase II metabolism and drug resistance have not been explored. This study demonstrates that fulvestrant up regulates the expression of UDP glucuronosyltransferase 1A4 (UGT1A4) >2.5- and >3.5-fold in MCF7 and HepG2 cells, respectively. Up regulation occurred in a time- and concentration-dependent manner, and was inhibited by siRNA silencing of ERα. Fulvestrant also up regulates multidrug resistance-associated proteins (MRPs). There was an up regulation of MRP2 (1.5- and 3.5-fold), and MRP3 (5.5- and 4.5-fold) in MCF7 and HepG2 cell lines, respectively, and an up regulation of MRP1 (4-fold) in MCF7 cells. UGT1A4 mRNA up regulation was significantly correlated with UGT1A4 protein expression, anastrozole glucuronidation, ERα mRNA expression and MRP mRNA expression, but not with ERα protein expression. Genetic variants in the UGT1A4 promoter (-163A, -217G and -219T) reduced the basal activity of UGT1A4 by 40-60%. In silico analysis indicated that transcription factor c-Myb binding capacity may be affected by these variations. Luciferase activity assays demonstrate that silencing c-Myb abolished UGT1A4 up regulation by fulvestrant in promoters with the common genotype (-163G, -217 T and -219C) in MCF7 cells. These data indicate that fulvestrant can influence the disposition of other UGT1A4 substrates. These findings suggest a clinically significant role for UGT1A4 and MRPs in drug efficacy.

Lack of correlation between in silico projection of function and quantitative real-time PCR-determined gene expression levels in colon tissue.

There are a number of in silico programs that use algorithms and external web sources to predict the effect of single nucleotide polymorphisms (SNPs). While many of these programs have been shown to predict accurately the effect of SNPs in functional areas of the gene, such as 5' upstream or coding regions, empiric research may be warranted to confirm the functional consequences of SNPs that are predicted to have little to no effect. We compared predictions from FASTSNP (Function Analysis and Selection Tool for Single Nucleotide Polymorphism) and F-SNP (Functional Single Nucleotide Polymorphism) with experimentally derived genotype-phenotype correlations to determine the accuracy of these programs in predicting SNP functionality. We used normal colon tissue to evaluate 24 TagSNPs within six genes. Two of 16 SNPs that were predicted to have no functional effect in FASTSNP were significantly associated with gene expression. Only one of the eight SNPs that were predicted to have a low to high effect was significantly associated with gene expression. While the two in silico programs that were used were similar in their results for the SNPs predicted by FASTSNP to have no effect, of SNPs with scores from low to high, there were three that received an F-SNP score below what is considered functionally significant. In silico programs can fail to identify functional SNPs, supporting a continuing role for empiric analysis of SNP function. Laboratory analysis is necessary to identify causal SNPs accurately, establish biological plausibility of the effect, and ultimately inform cancer prevention strategies.

Potential role of UGT1A4 promoter SNPs in anastrozole pharmacogenomics.

Anastrozole belongs to the nonsteroidal triazole-derivative group of aromatase inhibitors. Recently, clinical trials demonstrated improved antitumoral efficacy and a favorable toxicity with third-generation aromatase inhibitors, compared with tamoxifen. Anastrozole is predominantly metabolized by phase I oxidation with the potential for further phase II glucuronidation. It also, however, is subject to direct N-glucuronidation by UDP-glucuronosyltransferase 1A4 (UGT1A4). Anastrozole pharmacokinetics vary widely among patients, but pharmacogenomic studies of patients treated with anastrozole are sparse. In this study, we examined individual variability in the glucuronidation of anastrozole and its association with UGT1A4 promoter and coding region polymorphisms. In vitro assays using liver microsomal preparations from individual subjects (n = 96) demonstrated 235-fold variability in anastrozole glucuronidation. Anastrozole glucuronidation was correlated (r = 0.99; P < 0.0001) with lamotrigine glucuronidation (a diagnostic substrate for UGT1A4) and with UGT1A4 mRNA expression levels in human liver microsomes (r = 0.99; P < 0.0001). Recombinant UGT1A4 catalyzed anastrozole glucuronidation, which was inhibited by hecogenin (IC50 = 15 µM), a UGT1A4 specific inhibitor. The promoter region of UGT1A4 is polymorphic, and compared with those homozygous for the common allele, lower enzymatic activity was observed in microsomes from individuals heterozygous for -163G

Sulfation of 4-hydroxy toremifene: individual variability, isoform specificity, and contribution to toremifene pharmacogenomics.

Toremifene (TOR) is a selective estrogen receptor modulator used in adjuvant therapy for breast cancer and in clinical trials for prostate cancer prevention. The chemical structure of TOR differs from that of tamoxifen (TAM) by the presence of a chlorine atom in the ethyl side chain, resulting in a more favorable toxicity spectrum with TOR. In addition, some patients who fail on TAM therapy benefit from high-dose TOR therapy. Several studies have indicated that functional genetic variants in the TAM metabolic pathway influence response to therapy, but pharmacogenomic studies of patients treated with TOR are lacking. In this study, we examined individual variability in sulfation of 4-hydroxy TOR (4-OH TOR) (the active metabolite of TOR) in human liver cytosols from 104 subjects and found approximately 30-fold variation in activity. 4-OH TOR sulfation was significantly correlated (r = 0.98, P < 0.0001) with ß-naphthol sulfation (diagnostic for SULT1A1) but not with 17ß estradiol sulfation, a diagnostic substrate for SULT1E1(r = 0.09, P = 0.34). Examination of recombinant sulfotransferases (SULTs) revealed that SULT1A1 and SULT1E1 catalyzed 4-OH TOR sulfation, with apparent Km values of 2.6 and 6.4 µM and Vmax values of 8.5 and 5.5 nmol x min(-1) x mg protein(-1), respectively. 4-OH TOR sulfation was inhibited by 2,6-dichloro-4-nitrophenol (IC50 = 2.34 ± 0.19 µM), a specific inhibitor of SULT1A1. There was also a significant association between SULT1A1 genotypes and copy number and 4-OH TOR sulfation in human liver cytosols. These results indicate that variability in sulfation could contribute to response to TOR in the treatment of breast and prostate cancer.

Sulfation of fulvestrant by human liver cytosols and recombinant SULT1A1 and SULT1E1.

Fulvestrant (Faslodex™) is a pure antiestrogen that is approved to treat hormone receptor-positive metastatic breast cancer in postmenopausal women. Previous studies have demonstrated that fulvestrant metabolism in humans involves cytochromes P450 and UDP-glucuronosyltransferases (UGTs). To date, fulvestrant sulfation has not been characterized. This study examined fulvestrant sulfation with nine recombinant sulfotransferases and found that only SULT1A1 and SULT1E1 displayed catalytic activity toward this substrate, with K(m) of 4.2 ± 0.99 and 0.2 ± 0.16 µM, respectively. In vitro assays of 104 human liver cytosols revealed marked individual variability that was highly correlated with ß-naphthol sulfation (SULT1A1 diagnostic substrate; r = 0.98, P < 0.0001), but not with 17ß-estradiol sulfation (SULT1E1 diagnostic substrate; r = 0.16, P = 0.10). Fulvestrant sulfation was correlated with both SULT1A1*1/2 genotype (P value = 0.023) and copy number (P < 0.0001). These studies suggest that factors influencing SULT1A1/1E1 tissue expression and/or enzymatic activity could influence the efficacy of fulvestrant therapy.

Proteases and lipoprotein receptors in Alzheimer's disease.

Alzheimer's disease (AD) is the leading cause of senile dementia, and is a complex disorder. The pathological hallmarks of AD were discovered by Dr. Alois Alzheimer in 1907, and include deposits of amyloid or senile plaques and neurofibrillar tangles. Plaques are composed of a peptide, termed the Abeta peptide, that is derived by proteolytic processing of the amyloid precursor protein (APP), while neurofibrillar tangles result from a hyperphosphorylation of the tau protein. Mechanisms associated with the formation of plaques and neurofibrillar tangles and their respective contributions to the disease process have been intensely investigated. Proteolytic processing of APP that results in the generation of the Abeta peptide is now well understood and is influenced by several proteins. Recent evidence suggests that the Abeta levels are carefully regulated, and several proteases play an important role in removing the Abeta peptide. Finally, it is becoming apparent that several members of the LDL receptor family play important roles in the brain, and may modulate the course of AD.